A new posture monitoring system for preventing physical illness of smartphone users

With the widespread use of smartphones, users tend to use their smartphone for a long period of time in unhealthy postures; bending forward the neck and watching the relatively small screen closely with concentration. If users keep such unhealthy postures for a long time, they are susceptible to musculoskeletal disorders and eye problems such as cervical disc and myopia, respectively. To prevent users from having these diseases, we propose a new methodology to monitor the posture of smartphone users with built-in sensors. The proposed mechanism estimates various values representing user postures like the tilt angle of the neck, viewing distance, and gaze condition of the user, by analyzing sensor data from a front-faced camera, 3-axis accelerometer, orientation sensor, or any combination thereof, and warns the user if estimated values are maintained within the abnormal range over the pre-defined time. As a proof of concept, we developed an Android application named Smart Pose which estimates the user's neck tilt angle from analysis of the facial image, shakiness and tilt angle of the smartphone, and then notifies the user when her/his neck tilt angle is maintained in an unusual range during the smartphone operation. Also, we validated the result of our system by the comparison with measurements from 3D posture imaging equipment in our research facility. Via the proposed mechanism, a participant was able to be aware of his unhealthy postures, and then try to correct them.